The present invention relates in general to an improvement in gate valves which assures full through flow with no line obstruction when fully open and eliminates the need of packing, stuffing boxes, and packing glands to prevent leakage in any of its selected control positions whether used as an in-line shut-off valve or as a spigot or take-off point valve mounted on the side of a pipeline. While intended primarily for the control of abrasive slurries, including tailings, spigotting, hydrocyclone feed shut-off valving, slurry pump isolation, and dump valve applications, the valve can be used wherever gate valve control may be desired to close against line pressures up to 100 pounds per square inch. It further provides a face-to-face dimension equal to that of a standard 125 lb. gate valve, employees an inlet flange connection meeting 150 lb. ASTM-A181 Grade 1 Specifications and optional outlet connections of flange, Victaulic or plain end type meeting these same specifications. It further accomodates lever, handwheel, or air cylinder actuators with equal facility.